Beachwood and Pine Beach offer scenic views along the Toms River. Free parking is available at the Beachwood Yacht Club and can be found at using 145 Compass Ave, Beachwood, NJ 08722 in a GPS.
Bayside Ave and Riverside Dr are horizontal to the water, some portions have boardwalk trails along the water, but they are short and not continuous. This area is relatively flat and very residential. There are many towns connected together which would be great for longer distance runs.
Pros: Scenic, flat, minimal traffic, lots of businesses available for restrooms and drinks
Cons: Cannot think of any!